A novel five-level single phase grid connected converter for renewable distributed systems

In low-power grid connected systems (renewable or traditional energy sources) a single phase converter is usually adopted. In order to reduce losses, costs and size the keyword is removing any kind of transformer. This paper deals with a novel five level converter topology that follows this trend. The proposed converter architecture is based on a full bridge topology with two more power switches and two diodes connected to the midpoint of the DC link. Since the two added levels are obtained by the discharge of two capacitors, the balancing of the midpoint voltage is taken into account. Simulation and experimental results show the effectiveness of the proposed solution.